AuthorTopic: Building the CalderCraft Imara (Read 92551 times)

I couldn't resist and printed two of the parts for the mast (the middle two of four). This took about 2 hours and despite my skepticism turned out well. I don't know yet if my calculations and CAD conversions added up, the parts are still cooling down. Will check that out tomorrow.

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

You are doing a fab job there Dom! The lifeboat platforms and steering box are lovely pieces. If the metal parts are cast in a centrifugal mould then the misalignment is often caused by the mould being spun too fast. Moulds will indeed harden and erode over time becoming very hard in extreme cases especially in the centre reservoir area. Mould replacement needs keeping on top of, and if the company has their own press then isn't too expensive to do unless they are using very large moulds.

10 kilos Wow. You wouldn't happen to have a couple of pictures to show, would you?

While I'm waiting for the airbrush kit to arrive, I decided to clean up my workbench a bit. While I always try to maintain a certain level of tidiness, there's always some stuff cumulating over time.I thought I might as well give you a small tour of my workshop while I'm at it

I have an old closet where I store some tools and also the parts of the model kit that are yet to be built, painted, glued... and also some other bobs and pieces I have no idea where else to put.You can see my ever growing collection of glue, the weathering kit (weatherall, rustall, and scenic rust, amongst other things). In another compartment I keep my Dremel kit, circular saw, lab power supply, drills and what not. We also keep a big refrigerator in one corner of this room which prevents me from expanding all the way to the right, but that's not necessarily a bad thing

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Meanwhile, all 5 parts of the mast are printed. They came out very well, I only had to re-print one part once because the groove was not deep enough. Had to quickly go back to the drawing board.I printed the parts in Tough PLA, a new material that is as easy to print as regular PLA but stronger and less brittle.The segments have holes in them to better align them with short rods and also to improve mechanical stability at the joints.Glued everything together and I think it came out pretty straight. Only the top element seems to be slightly slanting, but I may be able to amend that by heating and bending it slightly.Some filling and sanding will be necessary, of corse.

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

I just inaugurated my new airbrush kit and the spraying cabin. I guess there's a steep learning curve in using this tool properly, but already i think from these two easy parts that I used as guinea pigs that the surface gets a lot more even than with anything I ever could achieve using brushes.The flagstaff is now painted and glued in place, as are the fire hydrants and the aft steering box.I also spray painted the upper water tank (using up my supply of Tamiya rattle cans) and encountered a small problem when a bug decided to land on the wet surface

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

The superstructure is looking really sharp,super work Dom.I recently downloaded the free emachineshop CAD software from Shapeways site with the idea of having a few parts printed by them.Been too busy building the big bits to have a go with it yet.It seems fairly simplistic,but that suits me.Last time I used CAD was at college in the late 80's and that was with one of the first 3D modeling programmes.I had hoped some of the items might be listed on the shapeways inventory,they may be,but gave up for now when I had spent 3 hours trolling through stuff

I don't know emachineshop CAD, but will check it out one of these days... I'm using TinkerCAD, which is also free and it runs in your web browser. So no need to install any programs. It was the only program that I could use from the go. Ostensibly it's fairly simplistic, but it's also powerful and, most importantly, intuitive to use - at least for me. You can't do organic models (like faces and stuff), but for mechanical and geometrical parts it's pretty easy to use.I only knew my way around 2D vector graphics (CorelDraw, Inkscape and the like) and apart from the additional dimension, I felt right at home with TinkerCAD. I also test ran some other programs (can't remember their names) but was all but lost.

In the dry-dock today, I painted the inside of the large cowl vents (using a paintbrush since I didn't knew how to to mask it off for airbrushing).When soldering resistors, I always put the lengths of "legs" that I cut away aside to use them for wire bridges. They came in handy today for making some handles for the fire buckets. I bent them around a 9mm drill and using needle-nosed pliers, I bent the ends to fit into the bucket holes.I then filled the buckets with some epoxy with a faint bluish tint to emulate water.

Dom

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

So Dom says.......'then filled the buckets with some epoxy with a faint bluish tint to emulate water' ...

With the warm weather you are experiencing the evaporation may be a little high....so that is why [on ships] they fill the buckets with sand

Scale sand?.... maybe try a model train supplies shop .....just put a small heaped dusting over the epoxy.....then the finest wisp of a Polyurathane spray to seal the top surface [with your new airbrush]

Derek_________________

PS...that is a very snazzy model sized vacuum spray booth......

1. is it a commercially produced unit?2. does it connect to a domestic vacuum cleaner?3. can you get a miniature Lazy Suzan rotatable table for it?

[If the answer to each is yes, this would then alow your neighbour Danielle [also from Switzerland] to spray paint in her kitchen

1. is it a commercially produced unit?2. does it connect to a domestic vacuum cleaner?3. can you get a miniature Lazy Suzan rotatable table for it?

1.: Yes, it is indeed. This is where I got it.2.: No, it comes with its own blower which connects to a length of flexible tubing. I simply hang the latter out the window when in use. The whole thing is a tad bulkier than I have anticipated, but I stow it away under the table (next to the airbrush compressor) when not in use. BTW, I would also highly and strongly advise against using a vacuum cleaner to aspirate any flammable fumes like from spray painting!3.: You can't see it very well on the picture I posted above because it is black, but there's one inside the cabin under the round(ish) piece of paper. It comes with the booth.

Dom

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Sand.So I went to the local grocery store and beelined to the pet food corner to grab a pack of bird sand. After sieving a portion through a tea sieve to get rid of the larger seashell and cuttlebone fragments, I was left with some fine grained sand. I used clear canopy glue to glue the sand on top of the epoxy. The sand may be a bit on the light side, color wise, but once the glue cures, it should darken things a bit. At least that is my theory Since I got one bucket too many, I left that one with "water" for the crew to swab the deck.

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

I wouldn't trust that Fireman Freddy....you know the old story, 'that most Fireman were pyromaniac's as youngsters'.... don't you

1. So if sand is silica, why not try adding a table spoon [from the 1,998 kg of sand left for some color tests] and mix it with another table spoon of common salt, then sprinkle this into a little red bucket........then pour a teaspoon of strong tea from your teacup........let it evaporate & the sandy tannin colour will remain

If you are happy with the colour...try the next logical step

2. mix 1 tablespoon of sifted silica + 1 tablespoon of common salt + 1/2 a table spoon of sugar....then sprinkle this into a little red bucket........then pour a teaspoon of strong tea from your teacup........let it evaporate & the sandy tannin colour will remain

The sugar when evaporating and whilst returning to it's original crystalline state will also coat each of the silica and salt granules as a binder & stick the mass as one ....so no need for polyurathane spray

Another batch of white metal parts grated, filed and sanded. This lot contains pulleys for the steering chain, some parts for the mast and a couple of assorted bits and pieces.I also gave the mast a first tentative sanding. I have not yet decided on the best sequence to fit everything together without one job getting in the way of the next (wires, lamps, filling, sanding, painting, soldering, fitting the fittings et cetera). I guess I will actually have to sit down and make a plan to figure this out.

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

I'm getting pretty good at making tapered masts with my 3D printer. The yard for the main mast was a bit challenging as it is rather delicate. First I tried to print it in only two parts, but at 4mm at the base and 2,5 mm at the top with 7,5 mm height each and a 1,5 mm bore, that was just pushing it. After approx. 5 cm height, the print failed. The parts were just too delicate and labile. So back to the drawing board and breaking up the yarn into 4 pieces of about 3,75 cm each.Printingall four parts simultaneously at a relatively low speed to give the material enough time to cool down between layers did the trick. Using the tried and tested method of inserting a length of 1,5 mm steel rod for additional strength between the parts left me with a minimum of filling and sanding.

Apart from this, I'm painting and fitting the parts for the steering linkage and some other stuff. I darkened the steering chain using Ballistol brass dye. If I only knew about this method back when I painted the anchor chains

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Steering linkage chain is now complete. I noticed a small problem... the pulleys for the chain will be in the way of the life boat davits... as they are supposed to line up with the small flagstaff mast thing. They will end up offset a bit, no other way of doing this now, I'm afraid. As noticed earlier, the deck structure is a bit shorter than it is supposed to be according to the plans and layouts. Oh well, not a big deal, but a bit annoying none the less.

The yarn is ready for priming. I'm waiting for some thin copper wire (0,1mm) for the mast lights that I have ordered. The wire I bought some months ago turned out to be too thick for this job (0,3mm) since I need to fit 6 wires into the mast (well, technically I could use only 4, but that would make the soldering a bit too complicated with the tiny SMD LEDs I'm using).

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Once again I found myself replicating some white metal parts from the kit with the 3D printer. This time I went for the lamp pedestals. There was nothing wrong with the white metal parts this time, but since I'm going to fit the lanterns with SMD LEDs, I was a bit afraid that the white metal base, being conductive, may short my circuit. So better safe than sorry and go with plastic. The prints turned out very well and I already designed them with a 4 mm hole for the SMD LED. They will need some minor sanding to rid them of the ripples from the print.

Meanwhile on the mast, I pulled in the six copper wires and secured them with super glue. Next up will be filling and sanding the wire groove.

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Some more progress on the mast. The wire groove is now filled and sanded and everything glued together.I made two small mistakes, though. The super glue on the lowest ring cured before I got it aligned the right way, so the four lugs are not symmetrically positioned. Not a big deal since this ring doesn't hold any cables, only some kind of bolts. And second, I put on the yard mast the wrong way around, so the small gap in the white metal cleat is facing up instead of down. Also not a biggie, just a bit irritating

And when was the last time you had a great idea that felt like a, well, really brilliant idea on paper at the time but turned out to be kinda stupid in practice? Well, I just had one of these today when I thought it was a good idea to protect the tiny and delicate copper wires for the lamps from physical stress by sticking them between two pieces of duct tape. Yes, stupid, I know (now) I eventually got them out of the sticky mess and I sure hope they are still OK

Next up priming and painting and then fitting the lights.

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Hey guys, what's cooking? After two weeks of vacation at the German North Sea I'm back in the shop. Airbrushing the mast, worked a treat. The base is not yet painted (green) and after that it needs a couple coats of matte varnish.Unfortunately the wires for the topmost lantern broke off right at the mast from manipulating them a bit too often... bummer. No way to fix this now. And just as I was in the process of protecting the points where the wires exit the mast with a drop of glue. Oh well, if I'm not mistaken, the topmost light would only be lit if she was towing, right?

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Mast is done After painting, varnishing and fitting the lamps I gave the lights a test run. As mentioned above, the topmost light ain't working because I accidentally broke the delicate wires. But as the thirt light would only be lit when towing, this actually adds a touch of realism After test fitting the mast and making the electric connections to the resistor board below deck, it was showtime: Using a line laser, I aligned the mast and then glued it in place.I think she slowly starts to look like a ship, don't you think?

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

D#mnit, the forum software just ate a quite lengthy post of mine... I really should remember to copy my texts before hitting the send button

Anyway, I went on with the captain's wardroom (or whatever this is called) and the kitchen. Must have been a rather cramped space on the real vessel.After sanding all of the parts I tentatively put them together with some tape to see what goes where. Since the plans are of not much help there, I pulled some pictures from other Imara builds off the web, that helped a lot.I think this is how it's supposed to fit together. Strange thing is that the front wall seems to be a tad too long. Since everything else seems to fit quite well, this makes me wonder.Maybe I'll give it another thought and a head scratch or two after a good night's sleep.After that it's glazin' and gluin' time...

Dom

Logged

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan